1. Field of the Invention
The present invention relates generally to a controlling apparatus for an air conditioner. More particularly, the present invention relates to a controlling apparatus for an air conditioner including the improved structure of an interface circuit adapted to exhibit excellent properties when a remote controller is attached to a main body of the air conditioner. Further, the present invention relates to electric circuit for the controlling apparatus which assures that each switch disposed separately from the main body of the air conditioner can effectively be actuated.
2. Background Art
A typical conventional controlling apparatus of the foregoing type employable for an air conditioner is disclosed in an official gazette of Japanese Patent Laid-Open Publication No. 3-233247. According to the prior invention, the controlling apparatus is constructed such that it is mounted on a main body of the air conditioner and an operation to be performed by the air conditioner is controlled by actuating a selection switch disposed on the controlling apparatus in response to an operation command signal outputted from the controlling apparatus for the air conditioner in association with a compressor and a blower.
With the conventional controlling apparatus for an air conditioner constructed in the above-described manner, because of the fact that the selection switch is disposed on the main body of the air conditioner, when an operation of the air conditioner is started, it is necessary that a user walks to the main body of the air conditioner with his own feet.
In the case that the selection switch is separated from the main body of the air conditioner and then disposed at the position where each user can conveniently actuate the selection switch, it is necessary that components such as relays, transformers or the like are additionally arranged for the air conditioner to improve the structure of each electric circuit. Consequently, there arises a problem that manhours required in association with electrical works conducted for installing the air conditioner increase.
In addition, in the case that an operation to be performed by the air conditioner is controlled by utilizing signals outputted from the existent temperature controlling unit, when a plurality of semiconductor elements for controlling the compressor and others incorrectly match with signals outputted from the temperature controlling unit, there arises another problem that the air conditioner is erroneously operated.